I think it’s always because the absolute value is always positive.
The correct answer is the first choice, ($1818.30, $5077.70.)
To find this, we first find the z-score based on the confidence level:
Convert 95% to a decimal: 95%=95/100 = 0.95
Subtract from 1: 1-0.95 = 0.05
Divide by 2: 0.05/2 = 0.025
Subtract from 1: 1-0.025 = 0.975
Using a z-table (http://www.z-table.com) we see that this value is associated with a z-score of 1.96.
Next, we identify

Next we find

Next we find

Next, we multiply this value by z:
1.96(831.479) = 1629.70
The confidence interval is given by
$5 because %15 of $70 is 10 and %5 of $10 is 5
Answer: B.
Step-by-step explanation: Remember, circumfrence is 2 pi r. multiply 6.1 and 2. That is 12.2. Then, use a calculator to multiply that to get approx 76.65. Round that up to 76.7.